The oldest and most widely used treatment procedure for water as supplied to municipalities or industrial sites or for wastewater as produced by these same entities, is to subject the liquid to a sedimentation process. Such systems usually comprise a confined area or basin with means for regulating the inflow of liquid thereto as well as to collect and carry away the treated effluent after a nominal detention time in the basin, during which suspended matter is given an opportunity to settle or separate by gravity from the liquid being treated.
The surface loading rate of conventional sedimentation basins can be dramatically increased by installing inclined parallel plates which effectively increase the surface area on which suspended particles may settle. These devices also promote laminar and stable flow conditions, which leads to a very high degree of separation. Conventional settling basins can be retrofitted with a plurality of inclined, parallel plates or baffles between which the influent is directed to encourage the separation of particles from the liquid. These particles impinge upon the baffle surfaces, congregate with other particles as they slide down the baffle surfaces, form larger particles and eventually fall by gravity to the basin bottom wherein they are periodically removed as a sludge product.
Several shortcomings have been apparent with many existing inclined plate settlers. The baffles or plates themselves are relatively expensive and the usual rigid construction of glass fiber reinforced plastic results in a member which accordingly must be limited in size and which tends to warp, become brittle and break off into pieces over time. Manipulation of such plates during installation, removal and repair is quite awkward. Also, settler plates are mounted in a fixed manner, thereby precluding ready variation of the angle of inclination to maximize sedimentation rates under altering conditions. The cleaning or replacement of any of the plates is a tedious procedure resulting in a significant amount of down-time.